The invention relates generally to shaped bodies such as slabs, sheets, profiles, tubes, pipes, foils and the like, as well as to a process for making shaped bodies. More particularly, the invention relates to coal-containing shaped bodies and a process of making the same.
The possibility of employing coal in the manner of plastics in order to make various articles has been discussed with reference to lignite in a publication by F. Fisher, O. Horn and H. Kuster found in "Brennstoff-Chemie", Volume 15, page 327 (1934). On the other hand, from a publication by C. Kroger and G. Brinkmann in "Brennstoff-Chemie", Volume 48, number 6, pages 173-184 (1967) and number 7, pages 198-206, it is made clear that the binding power of pure coal is too low for obtaining useful shaped bodies, even if pressure and high temperatures are employed in the shaping operation. Thus, after cooling, the shaped bodies do not possess adequate bending strength. For instance, although a maximum compressive strength of 5885 to 7845 newtons per square centimeter (600 to 800 kp per square centimeter) is obtainable when using coal having a volatile components content of 32%, the bending strength, on the contrary, is extremely low. Moreover, when using pure coal, a considerable change in the dimensions of the shaped bodies occurs during cooling.